1. Field of the Invention
The present invention relates to an image processing apparatus. More particularly, the present invention relates to an image processing apparatus for executing processing based on whether or not scanned image data contains a predetermined pattern, and a control method thereof
2. Description of the Related Art
In recent years, there have been remarkably improved an image processing technique and an image forming technique.
In response to the aforementioned circumstances, there has been practically used an image forming apparatus having a function of identifying special documents such as bills and securities to thereby prohibit illegal copy of such documents.
In addition, there have been disclosed various techniques for prohibiting illegal copy of papers and authors utilized in an office.
For example, Japanese Laid-Open Patent Publication No. 07-273975 discloses the following technique. That is, a digital copying machine determines whether or not image data scanned by a scanner contains a confidential numbering pattern. If the image data contains the confidential numbering pattern, the digital copying machine masks the image data to output a blank sheet.
In addition, Japanese Laid-Open Patent Publication No. 2004-228897 discloses an image processing method of embedding a base pattern including copy permission information as a background image in advance and permitting to copy a document to the user who is decided based on a permission condition corresponding to the copy permission information, in a copying machine or the like.
As described above, information is embedded into a document and image processing is performed based on the embedded information, so that illegal copy of papers and the like can be prohibited.
However, if a document is copied plural times, information embedded into the document is degraded gradually. More specifically, if a document with the aforementioned information embedded thereinto is copied plural times, the embedded information to be recorded in a duplication is degraded. When the duplication with the degraded information embedded thereinto is further copied, there is a possibility that the information can not exert a function of prohibiting illegal copy due to degradation.
That is, in the conventional art, if a document is copied plural times, there is a possibility that illegal copy of the document can not be prohibited with certainty.
A technique for controlling image processing based on information embedded into papers is important for various purposes in addition to prohibition of illegal copy of papers and the like. Therefore, it is necessary to develop a technique for copying a document having information embedded thereinto and, also, to develop a technique for embedding information into a document.
The present invention is devised in view of the aforementioned circumstances. A first object of the present invention is to provide an image processing apparatus capable of avoiding the following disadvantage: when a document is copied repeatedly, a function of information embedded into the document is degraded in a duplication of the document, and a control method thereof
A second object of the present invention is to provide an image processing apparatus capable of devising embedment of information into image data, thereby utilizing information embedded into a document with certainty, and a control method thereof.